Gone as in how? You don't see them in the menu? They are not available in the computer, are they not in the font manager? How can it be a bug if you/we don't know if it's and indesign or OS issue? How can adobe fix a bug with that information to go by?
we can only go with the information you provide. If you really want help elaborate.
Are you, by any chance, using a font utility program such as FontExplorer to manage your fonts? If so do you have it set up to auto-activate your fonts when you open an InDesign file? If that is the case then go to the Plug-in Manager (accessed through the Tools menu for FontExplorer) and check that "Deactivate fonts that have been activated by Plug-ins when requesting application quits" is not checked. If it's checked then uncheck it.